Evaluation and structure-activity relationship study of acute toxicity of naphthoquinones to Photobacterium phosphoreum, Photobacterium T3B.

The acute toxicities of five naphthoquinone compounds to Photobacterium phosphoreum were determined. We evaluated the mechanism of toxicity using the structure-activity relationship technique. The results showed that some factors, including the species of substituents, shape/size of molecule and oil-water partition coefficient (log P) played the important roles in the interaction between the naphthoquinones and the target. Among of these, the toxicities of Atovaquone and Buparvaquone were lower than the other naphthoquinones we tested because of the alkyl-substitution with the bigger volume and strong hydrophobicity. Conversely, Menadione had the highest toxicity because of the appropriate log P and shape/size of molecule resulting in the easier interaction with the target.